From cff059a07858c58e461b3e7dcc865d302e9fd04c Mon Sep 17 00:00:00 2001 From: "W. Trevor King" Date: Wed, 26 Nov 2008 16:26:51 -0500 Subject: [PATCH] Changed guessed Q from 5 to 1, which gives about the right breadth. I'm dubious about the fit quality though. Looking at the fit.log output after looking at the 20080919_cantA_tweak.vib data again reveals After 4 iterations the fit converged. final sum of squares of residuals : 9.6001e+08 rel. change during last iteration : -2.46003e-07 for the first curve, and similar residuals (and exactly 4 iterations) for the other curves. Hmm. I should probably explicitly show the range of frequency space I'm fitting in. --- calibcant/vib_analyze.py | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/calibcant/vib_analyze.py b/calibcant/vib_analyze.py index 6fb1615..cfa2c3e 100755 --- a/calibcant/vib_analyze.py +++ b/calibcant/vib_analyze.py @@ -157,8 +157,8 @@ def fit_psd(freq_axis, psd_data, minFreq=500, maxFreq=7000) : # peak height = C / (3 x_res^4 + A^4) # Q = A/B # - # guess Q = 5, and adjust from there - Q_guess = 5 + # guess Q = 1, and adjust from there + Q_guess = 1 # so x_res^2 = B^2 Q^2 - B^2/2 = (Q^2-1/2)B^2 # B = x_res / sqrt(Q^2-1/2) if config.TEXT_VERBOSE : -- 2.26.2